Adaptive immunity Flashcards
Where do T cells mature?
Thymus gland
What is the function of B cells?
Produce antibodies (immunoglobulins)
What is the function of helper T cells?
Secrete cytokines that activate other immune cells
What is the function of cytotoxic T cells?
Directly kill infected cells and tumour cells
Describe 3 ways in which antibody binding to an antigen can aid in the removal / destruction of pathogens.
Block a pathogen from causing harm
Mark a pathogen for phagocytosis (opsonisation)
Activate the complement system
Which feature of antigens means that different antibodies can bind to separate parts of the same antigen?
Epitopes
What is clonal selection?
When B cells proliferate to produce clones of identical cells
Which cells are needed for the activation of B cells?
Helper T cells
What is the cell surface protein of cytotoxic T cells?
CD8+
What is the cell surface protein of helper T cells?
CD4+
What is the function of TH1 cells and what do they activate?
Secrete cytokines (interferon-y)
Activate virally infected cells, macrophages, and other T cells
What is the function of TH2 cells and what do they activate?
Secrete cytokines (interleukins)
Activate B cells
T cell receptors are composed of which 2 chains?
Alpha chain
Beta chain
On which cells are Class I MHC proteins found?
Which cells recognise Class I MHC proteins?
Which type of antigens to Class I MHC proteins present?
Most cells
CD8+ cytotoxic T cells
Intracellular antigens
Where are the peptides presented on MHC Class I proteins derived from?
Cell cytoplasm
Where are the peptides presented on MHC Class II proteins derived from?
Ingested material
What is the function of regulatory T cells?
Downregulate immune responses
B cells transform into what when activated?
Plasma cells
When B cells are activated to become plasma cells, which organelle dramatically increases in size?
Endoplasmic reticulum
Which type of bonds hold the light and heavy chains of antibodies together?
Disulphide bonds
What is the most abundant immunoglobulin in the blood?
IgG
What is the first immunoglobulin produced during infection?
IgM
During an infection, which type of antibody class switching occurs?
IgM to IgG
Antigens bind to which region of T cell receptors?
Variable domain (part alpha chain, part beta chain)
Which complex which aids in activation is associated with T cell receptors?
CD3 complex
On which cells are Class II MHC proteins found?
Which cells recognise Class II MHC proteins?
Which type of antigens to Class II MHC proteins present?
Antigen-presenting cells
CD4+ helper T cells
Extracellular antigens
Antigens bind to which region of Class I MHC proteins?
Alpha subunits
Antigens bind to which region of Class II MHC proteins?
Alpha and beta subunits
CD8 and CD4 proteins bind to which region of MHC proteins?
Non-variable domain
